Detection: Linux Root Execution of id

Description

The following analytic detects the execution of the id command by the root user on Linux systems. Attackers commonly run id during post-exploitation to confirm they have achieved root-level privileges after a privilege escalation attempt. This activity is significant because it may indicate an attacker is verifying superuser access following a successful compromise. If confirmed malicious, this could signal that an attacker has gained full control of the system, enabling them to perform destructive actions, exfiltrate sensitive data, or establish persistent unauthorized access.

Search

 1
 2| tstats `security_content_summariesonly`
 3  count min(_time) as firstTime
 4        max(_time) as lastTime
 5
 6from datamodel=Endpoint.Processes where
 7
 8Processes.process_path="/usr/bin/id"
 9Processes.user="root"
10
11by Processes.process Processes.vendor_product Processes.user_id
12   Processes.process_hash Processes.parent_process_name Processes.parent_process_exec
13   Processes.action Processes.dest Processes.process_current_directory Processes.process_path
14   Processes.process_integrity_level Processes.original_file_name Processes.parent_process
15   Processes.parent_process_path Processes.parent_process_guid Processes.parent_process_id
16   Processes.process_guid Processes.process_id Processes.user Processes.process_name
17
18
19| `drop_dm_object_name(Processes)`
20
21| `security_content_ctime(firstTime)`
22
23| `security_content_ctime(lastTime)`
24
25| `linux_root_execution_of_id_filter`

Data Source

Name	Platform	Sourcetype	Source
Sysmon for Linux EventID 1	Linux	'sysmon:linux'	'Syslog:Linux-Sysmon/Operational'

Macros Used

Annotations

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Implementation

The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the Processes node of the Endpoint data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.

Known False Positives

Administrators and automated scripts routinely run the id command as root for system auditing or configuration tasks. Filter based on known administrative activity or trusted scripts.

Associated Analytic Story

• Linux Post-Exploitation

• Linux Privilege Escalation

• Linux Persistence Techniques

Intermediate Findings

Threat Objects

Detection Testing

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

Source: GitHub |

Version: 1